Secret vs. Hidden: Perception in Old School Play

Refined "Old School Search Procedure" 

1. Declare who is searching and number of turns spent to create initial dice pool

    • Clerics, Fighters, Halflings, Magic Users, Thieves add 1d6 per turn
    • Dwarves (underground) & Elves add 2d6 per turn
    • Only Elf, Dwarf (underground), & Thief hirelings add 1d6 per turn

2. Divide dice pool by squares being searched (round up). Max one square per dice.

3. Roll dice pool. A single 1 indicates a success.

Example:

A Fighter (1d6), Cleric (1d6), Elf (2d6), and Halfling (1d6) with two hirelings; a thief (1d6) and a dwarf (1d6) enter a 30'x30' chamber. Their "Search Pool" is 7d6.

DM: You enter an ancient chapel with a vaulted ceiling from the west. Profane tapestries raggedly sag from the walls, save one one the north wall to the left of the alter that looks almost new. The alter itself is basalt caked in grime that glistens crimson in your torchlight. Broken pews line the room. Another entry can be seen in the middle of the south wall.

Caller: We are going to spend 1 turn searching this room. I (Elf) specifically want to check out that tapestry, the Cleric is going to search the alter, and the halfling is rummaging through the pews.

DM: The room is 9 total squares so it cannot be entirely searched in 1 turn. Do you want to select 7 squares to search, or take 2 turns?

Caller: We will take 2 turns.

DM: I am rolling 2d6 (14 / 9 = 1.55 or 2). [Rolls 3, 5 - no success]. The tapestry elaborately depicts what looks to be prisoners being thrown off of a cliff into the shadowy jaws of some ancient beast. An inspection of the alter reveals heavy maroon book with silver lettering on the cover written in an infernal script that you cannot read. Among the pews you find a dead body, quite old but not as ancient as this place, in dark robes. Nothing else of interest is found. Do you want to do anything further with the tapestry, book, or body?

Elf: I want to look behind the tapestry.

Cleric: I cast detect evil on the book.

Halfling: I'll loot the body.

DM: When you reach out to move the tapestry there is a faint shimmer and your hand passes through it. It is clearly an illusion. The book most certainly radiates evil. The body has an ornate dagger with a black squiggly blade and a ruby set on the pommel along with a purse containing 7gp and 3sp.

Elf: I stick my head and torch through the tapestry to see what is on the other side.

Cleric: I'll leave that book alone.

Halfling: I'll take the dagger and the purse.

DM: On the other side of the tapestry a narrow 5' hall extends 30 feet north into darkness. As you pick up the dagger you feel your fingers tighten painfully around its hilt.

Halfling: Shit.

<End of Example>

I wrote the above example to show how the search procedure that I have begun using works in play, but then I realized it also demonstrates something else. A lot of ink has been spilled about "Perception Checks" in old school D&D. I frequent the r/OSR sub on Reddit and it is probably a top 5 discussion topic. As soon as someone asks the question they are assaulted with a chorus of "You don't! Player skill over Character skill! The answer isn't on your character sheet!" Heck, I bought that particular brand of Kool-Aid myself and I'm sure if you scrub through my comment history you'd find me singing that particular refrain.

One problem. I don't do it like that at my table. It is much more nuanced. After allowing it to take up more brain space than I probably should have, I'm ready to explore the topic here. It really comes down to do two similar, but fundamentally different, concepts: Secret vs. Hidden.

Secret: not known or seen or not meant to be known or seen by others.

Hidden:  kept out of sight; concealed.

Things that are secret AND things that are hidden are both not supposed to be found, however something that is secret was NEVER meant to be found. Something that is hidden was, presumably, at some previous point not hidden.

How are those differences presented in play?

A door behind a tapestry, a safe behind a hung painting, a hallway that has been walled off, or a trapdoor under a rug are hidden. They were not always concealed, they were once visible and then at a later point they were obfuscated. These things are easily identified through player skill. If a character looks behind the tapestry, removes the painting, breaks the plaster, or rips away the rug the true nature of the thing will be revealed.

The stone wall that slides away when the torch sconce is turned, the bookcase that swings open when you pull out the right book, and the desk compartment that pops open when the panel is pressed in just the right spot are secret. They were specifically designed to avoid detection, even under scrutiny. They were never meant to be found. These things require a roll, usually 1-in-6, to be found.

Back to the example the players found three hidden things because of their Player Skill. They found the hidden tunnel behind the illusory tapestry, they found the Book of Vile Rites, and they found the cursed Dagger of Sacrifice. These things were not readily apparent when they walked in the room and their descriptions of their actions revealed them. What they did not find was the secret sliding wall section on the east wall that is activated by pressing a certain stone on either side at the same time. For that they would have needed to pass their check.

It is important to note: Secret things should not be required to progress through the dungeon. On the other side of that sliding wall is some sweet loot, but not finding it will not impede forward progress through the dungeon.

Math behind the change on demihuman searching

Demihuman search abilities (dwarf, elf) detect secrets on 1-in-6 but they get to roll 2d6.  Mathematically rolling 1-in-6 on 2d6 has a 31% chance of success, and rolling 2-in-6 on 1d6 has a 33% chance of success. The difference is negligible (2.77%) but I think the change in approach can really increase speed of play by making search a single roll per room.

 In the example that 30'x30'x10' room had 900 square feet of floor, 900 square feet of ceiling, and 1,200 square feet of walls for a total of 3,000 square feet. To search it in its entirety it would have taken 30 total turns. With all six of them searching that would have been five turns.

If they ignored the ceiling (beyond maybe a cursory glance to make sure there were no murder holes) it still would have taken 4 (3.5) turns.

If they ignored the floor and they were just searching walls, as adventurers tend to do, they could do it in 2 turns. I'm throwing in the ceiling and floor for free because I'm not a dick.

Additionally, in those 2 turns they would have between a 17% and 33% chance of success on any of the 12 available 10'x10' surfaces searched to succeed. It becomes extremely important, and tedious, to know who is specifically searching which section.

Using the dice pool, the party took 2 turns and had a 30.56% chance of success, so slightly more generous than RAW which I attribute to the party working as a team.

"Hey dwarf, come over here and check out this stonework. What do you think?"

 

 

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